X-ray analysis of samples is a growing area of interest across many industries such as medical, pharmaceutical, and petroleum. Moving analysis from the laboratory to the field is becoming increasing popular for many reasons, including reduction in size and costs of analyzer components, as well as industry's continually increasing needs for better and faster data collection in areas remote from a laboratory (e.g., production lines, store shelves, raw material sites, mobile compliance vans, transportation and customs hubs, etc.). Moving sensitive instruments to these areas presents certain challenges, including shielding, sample presentation, vibration damping, etc. for which unique resolutions are in continuing demand.
For example, sample handling is of critical importance in such systems, as is x-ray shielding. It is a general requirement of x-ray analysis systems to minimize x-ray exposure during sample analysis, and also during loading and unloading. During sample loading, this can accomplished by interlock systems which mechanically and/or electrically control an x-ray blocking “shutter” mechanism over the x-ray source and/or a relay to a high voltage power supply powering an x-ray tube. An interlock system senses an operator opening the system to load/unload a sample, and automatically activates the shutter (or relay) to completely stop any x-rays from transmitting through the now-open sample door, toward an operator. Shielding during sample measurement is also required, and can be provided by sample covers, enclosures, shields and the like, and/or by creating adequate distance between the user and the x-rays.
Moreover, any sample insertion and removal technique should also present the sample to the x-ray measurement engine at a controlled distance (e.g., along a z-axis) for proper alignment to the requisite x-ray analysis spot. This z-axis alignment is critically important for x-ray optic enabled analyzers (such as the MWD XRF and ME EDXRF x-ray engines discussed below) because of the sensitivity of the measurement to the focal areas of one or two separate optics in the x-ray excitation and/or detection paths. For example, U.S. Pat. Nos. 6,934,359 and 7,072,439, hereby incorporated by reference herein in their entirety and assigned to X-Ray Optical Systems, Inc., the assignee of the present invention, disclose monochromatic wavelength dispersive x-ray fluorescence (MWD XRF) techniques and systems for the analysis of samples. Monochromatic excitation, energy dispersive x-ray fluorescence (ME-EDXRF) analyzers are also gaining wide market acceptance, as disclosed in, e.g., commonly assigned US Publication 2011-0170666A1 entitled XRF System Having Multiple Excitation Energy Bands In Highly Aligned Package, the entirety of which is hereby incorporated by reference herein.
Handheld x-ray analyzer configurations, which have been broadly marketed in the recent past, meet certain performance and regulatory criteria. However, certain jurisdictions are particularly strict on the “open beam” nature of handheld instruments; and certain practical constraints (i.e., long measurement times, high power usage, limited resolution) may limit their use in certain applications.
What is required, therefore, is a transport apparatus for an x-ray analyzer, which minimizes x-ray leakage during sample loading and measurement, provides precise alignment of a sample to an x-ray analyzer focal area, and provides more convenient, reliable, and protective transport for sensitive x-ray analysis equipment.